1. Field of the invention
The present invention relates to a steering column for a vehicle and a steering apparatus for a vehicle having the same. In particular, the present invention relates to a steering column for a vehicle in which a coupling position of a tilt bolt is positioned on the central axis of a steering shaft, so that bending is not caused and an adjustment lever does not hit a driver on the knee at the time of vehicle collision, and a nut opposite to the adjustment lever can be prevented from being loosened at the time of manipulating the adjustment lever.
2. Description of the Prior Art
As generally known in the art, a steering apparatus for a vehicle is an apparatus for allowing a driver to change the traveling direction of the vehicle in accordance with the driver's intention, thereby assisting the driver to freely change the center of rotation of the front wheels of the vehicle so as to make the vehicle travel in a desired direction.
Steering force produced in such a steering apparatus for a vehicle when the driver manipulates the steering wheel will be transferred to a rack and pinion mechanism through a steering shaft, and will finally change the orientation of the opposite front wheels.
In addition, a telescopic function or a tilt function may be additionally provided for such a steering apparatus for the convenience of a driver through a telescopic apparatus or a tilt apparatus, wherein the tilt apparatus serves to adjust the anchoring angle of a steering wheel, and the telescopic apparatus is formed by inserting a hollow tube into another hollow tube in such a manner that they can be extended or retracted in the axial direction. At the time of vehicle collision, the telescopic apparatus may serve to absorb impact energy by allowing the steering shaft and the steering column to be collapsed.
Consequently, a steering apparatus is classified into a telescope-type steering apparatus or a tilt-type steering apparatus according to the above-mentioned functions. If desired, it is possible to add the tilt function to the telescope-type steering apparatus. Through these functions, a driver may adjust the protrusion extent or inclined angle of the steering wheel to be suitable for his/her height or body shape.
FIG. 1 is an exploded perspective view showing a part of a conventional steering column for a vehicle.
As shown in FIG. 1, the conventional steering column for a vehicle includes: an outer tube 100 for receiving a steering shaft 175; an inner tube 170 introduced into the outer tube 100; a lower bracket 165 for fastening the inner tube to a vehicle body; an upper bracket 105 provided at the top side of the outer tube 100, and anchored to the vehicle body; a distance bracket 180 integrally fixed with the outer tube 100, and formed with a telescopic bore 185; at least one tilt bracket 150 united with the upper bracket, and formed with a tilt bore 110; a fixed gear 145 provided on an outer surface of the tilt bracket 150; a movable gear 140 engaged with or disengaged from the fixed gear 145; a tilt bolt 130 extending through the tilt bore 110; a cam 135 engaged with the movable gear 140; a washer 125 and a nut 120 for fastening the cam 130 and a adjustment lever 115; and a gear spring 142 interposed between the movable gear 140 and the fixed gear 145.
Tilt and telescopic operations may be executed by tightening or releasing the adjustment lever 115. If the adjustment lever 115 is tightened, the tilt bracket 150 is tightened, thereby applying compressive force to the outer tube 100 to such an extent that the outer tube 100 and the inner tube 170 come into close contact by the compressive force and no tilt or telescopic operation is executed. Whereas, if the adjustment lever 115 is released, the compressive force applied to the outer tube 100 and the inner tube 170 is removed, so that the tilt or telescopic operation is enabled.
The telescopic operation is completed by changing the position of the tilt bolt 130 along the telescopic bore 185 formed in the distance bracket 180 after the adjustment lever 115 is released, and then tightening the adjustment lever 115.
The tilt operation is completed by changing the position of the tilt bolt 130 along the tilt bore 110 after the adjustment lever 115 is released, and then tightening the adjustment lever 115.
At the condition in which the adjustment lever 115 is locked, the outer tube 110 and the steering shaft 175 are anchored. However, if the adjustment lever 115 is released, the outer tube 100 or the inner tube 170 may be tilted about a tilt center 160 by a cam 135, or the steering column may be axially extended or retracted.
The above-mentioned conventional steering column for a vehicle has problems in that since the coupling position of the tilt bolt is spaced downward from the central axis of the steering shaft, substantial bending may be caused at the time of vehicle collision, and since the adjustment lever is assembled at a position lowered by the coupling position of the tilt bolt, the adjustment lever may hit a driver on the knee at the time of vehicle collision, and a nut opposite to the adjustment lever may be loosened when the adjustment lever is manipulated.